(1) Field of the Invention
The present invention concerns coating com positions for producing watertight, vapor-permeable and flame-retardant coatings, processes for manufacturing textile support materials coated therewith, textile support materials coated with the coating composition, and use thereof.
(2) Description of the Related Art
To protect buildings from the ingress of water spun-bonded web materials composed of polypropylene fiber, polyester fiber or glass fiber have been coated with bitumen and similar tar products in order to obtain tear-resistant, water-repellant sheeting materials. The disadvantage of these materials is the low watertightness (a hydrostatic head of 200 mm according to DIN 53886) is coupled with a similarly low water vapor permeability (100 g/m.sup.2 .times.day) according to DIN 53122/1).
EP-A-64 630 discloses flame-resistant, halogen-free molding materials based on ethylene copolymers, bitumen, red phosphorus and Al(OH).sub.3 which can be used for manufacturing sealing sheets.
EP-B-18 691 U.S. Pat. No. 4 452 850) discloses roofing felts comprising a fabric coated on both sides with PVC. The disadvantages of this coating are the very low water vapor permeability of 8 m.sup.2 /g.times.day and the plasticizer migration.
DE-A-3 200 824 likewise concerns textile support materials coated with plasticizer-containing PVC, which have the abovementioned disadvantages. For flame resistance the fabrics used were made of polyester fiber modified to be flame-resistant.
DE-A-2 124 036 (CA-A-924 037) describes a low-flammability preparation comprising an ethylene/vinyl chloride/acrylamide copolymer and an ammonium polyphosphate, which can be used as binder for impregnating fiber webs.
DE-A-2 452 369 (CA-A-1 052 924) describes flame-resistant polymer lattices based on vinyl chloride/.alpha.-olefin/bishydrocarbyl vinylphosphonate, which can be used for coating fiber webs, inter alia. The coated fiber webs are likely to have only a low water vapor permeability.
DE-A-3 017 019 (U.S. Pat. No. 4 288 486) describes a sheetlike cover material based on a glass fiber mat which has been covered on at least one surface with a layer of mechanically foamed and then melted and compressed vinyl polymer (preferably polyvinyl chloride).
EP-A-176 849 (AU-A-8 547 976) mentions that, to improve the flame-resistant effect, inorganic solid particles can be incorporated into the support sheets for roofing felts. The action of these particles is based on the formation of a firm, skeletal carbonizing layer. The coating is designed to prevent the burning of holes into the roofing felt by flying embers.
It is an object of the present invention to make available a coating composition which is suitable for producing flame-retardant coatings, in particular on textile support materials, combining high water tightness with high vapor permeability. It is a further object to make available a process for manufacturing textiles coated therewith which shall combine a low basis weight and a high mechanical strength with the abovementioned requirements profile concerning flame resistance, water-tightness and vapor permeability.